Core B provides on-site technical expertise to install, maintain, and repair harware for: 1) traditional clinical testing of vestibular function by electronystagmography, bithermal caloric irrigations and posturgraphy; 2) novel tests of vestibular function by related balance function using powerful rotational and linear stimulators, eye movement recording by the magnetic coil technique, electromyography, and evoked potentials; and 3) digitally assisted, quantitative microscopy and micrography. Core B also provides support necessary to permit efficient use by researchers in all projects of: 1) locally developed software for eye and head analysis (MacEyeball); 2) database management and systematic backups of patient demographic, clinical and genetic data, digitally sampled eye and head movement data, and digital images; 3) general computer hardware and software networking, installation, and maintenance; and 4) digital processing of text and figures for publication. Core B provides all projects with immediate and reliable access to these essential services.